U.S.-based cybersecurity firm CrowdStrike said Chinese hackers were trying to break into U.S. technology and drug firms to steal their trade secrets the day after a new agreement with Washington to stop such actions.

CrowdStrike said it has thwarted at least seven attempts to break into computers used by U.S. companies since the September 25 agreement between U.S. President Barack Obama and his Chinese counterpart, Xi Jinping. The agreement said neither government would knowingly support cybertheft of corporate secrets to support domestic businesses.

Responding to the report, White House spokesman Josh Earnest said Obama made clear that the U.S. would judge China "not on words ... but on actions" regarding cybersecurity.

China's Foreign Ministry denied the allegations, saying Beijing "firmly opposed and cracks down on all forms of hacking" and is the victim of such intrusions. Ministry spokesman Hua Chunying said it is difficult to trace the origin of cyberattacks.

But a CrowdStrike representative said hackers are using tools and techniques that previously have been used by China-based hackers.

Hacking attacks hurt companies when they lose the commercial advantage of exclusive use of intellectual property that they have spent time, work, and money creating.

Cybersecurity firm FireEye said in a Web posting that firms may also face fines or lawsuits for failing to protect personal information, and that they're further damaged when customers lose confidence in a company's competence.